Application of Autologous Costal Cartilage Scaffold in Reconstruction of Microtia Ear

Objective To investigate the application effect and manufacturing skills of autologous costal cartilage scaffold in ear reconstruction for microtia.Methods From January 2016 to January 2019,41 patients with microtia reconstruction in our hospital were selected,all of whom were type II or type III pediatric deformities.All patients underwent auricle reconstruction and retroauricular skin expansion and autologous costal cartilage stent.The first stage of the operation is to insert a skin dilator behind the residual ear and inject water to expand.The second stage of the operation is to carve and repair the soft ribs(usually 6 or 7 ribs)from the body,make a three-dimensional auricle support for auricle reconstruction,place a negative pressure drainage tube,and follow up for 3 to 6 months to observe the three-dimensional shape of the reconstructed auricle and the formation of cranioauricular angle.Results 41 patients with microtia had good three-dimensional shape of auricle reconstruction,normal auricle position,moderate cranioauricular angle,good helix and triangular fossa structure,and good bilateral symmetry.Patients and their families were satisfied with the effect of auricle reconstruction.Conclusion Autologous costal cartilage is a good scaffold for auricle reconstruction.It is through efficient and elaborate carving and splicing that a good three-dimensional auricle structure can be formed.Combined with early flap expansion,a good postoperative appearance effect can be obtained,which is the appropriate method for auricle reconstruction at present.

Topology optimization of support structure of telescope skin based on bit-matrix representation NSGA-II

Non-dominated sorting genetic algorithm II（NSGA-II）with multiple constraints handling is employed for multi-objective optimization of the topological structure of telescope skin,in which a bit-matrix is used as the representation of a chromosome,and genetic algorithm（GA）operators are introduced based on the matrix.Objectives including mass,in-plane performance,and out-of-plane load-bearing ability of the individuals are obtained by fnite element analysis（FEA）using ANSYS,and the matrix-based optimization algorithm is realized in MATLAB by handling multiple constraints such as structural connectivity and in-plane strain requirements.Feasible confgurations of the support structure are achieved.The results confrm that the matrix-based NSGA-II with multiple constraints handling provides an effective method for two-dimensional multi-objective topology optimization.